David heston



(No Model.)

D; HESTON.

GREASE PRO0P PAPER.

No. 337,155. Patented Mar. 2, 1886.

N. Pain; Phmumo n har, Wuhingmm 0.1;

A NITED STATES PATENT Erica.

DAVID HESTON, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO BROWN, HES TON& 00., OF SAME PLACE.

vGREASE-PROOF PAPER.

SPECIFICATION forming part of Letters Patent No. 337,155, dated March 2,1886.

Applicationfilefl November 9, 1885. Serial No. 182,291 (No modclJ To aZZwhom it may concern:

Be it known that I, DAVID HESTON, a citizen of the United States,residing in the city and county of Philadelphia, State of Pennsylvania,have invented a new and useful Improvement in Grease-Proof Paper, whichimprovement is fully set forth in the following specification andaccompanying drawings, in which- Figure 1 represents a longitudinalsection of a piece of grease-proof paper embodying my invention. Fig. 2represents a face view thereof, the layers thereof being shown brokenaway.

Similar letters of reference indicate corresponding parts in the twofigures.

My invention consists of a grease-proof paper formed of sheets of paperand silicate of soda or other alkaline equivalent.

In carrying out my invention, I take sheets A B of paper and interposebetween the same a stratum, O, of silicate of soda or other alkalineequivalent, in a liquid condition, and roll the compound sheets of paperand alkali, or subject the same to pressure, whereby the parts arefirmly united as one.

In lieu of the above, I may take pulp, and, during the operation offorming thesameinto paper, introd uce alayer or stratum of the alkaliinto the pulp in such a manner that when the paper is produced it has astratum of the alkali interposed between the outside sheets, the paperin either case presenting the usual appearance of paper, admitting ofbeing printed, out, folded, 850. I

When the paper is in use for boxes, wrappings, 820., should a materialof greasy nature be placed against the same, the contiguous side of thepaper may become greased; but

the grease is prevented from passing through 0 the alkali; hence theopposite side of the paper or outside of the boxes, wrappings, 8rd,remains clean without the exhibition of grease.

In speaking of paper or paper-pulp from which the grease-proof paper ismade, I in- 45 clude all kinds of paper or paper-stock, or anycombination of materials of which paper or board is or may be made.

Having thus described myinvention, what I claim as new, and desire tosecure'by Letters 50 Patent, is

1. Greaseproof paper formed of paper, and an inner stratum of silicateof soda or other a1- kaline equivalent, substantially as described.

2. A grease-proof paper formed of layers 5

